Insulating end post



June 25, 1968 E. l... GROFF 3,389,859

INSULATING END POST Filed July 17, 1967 INVENT OR EMQRY L. GEOFF United States Patent ABSTRACT OF THE DISCLOSURE An insulating end post for railway rails wherein, the end post is made of filaments coated with thermo-responsive composition and made available in sheet form from which the profile of the end post is die cut.

This invention relates to insulating end posts used between adjacent ends of railroad rails to insulate one rail end from another in railway block systems, and a method of making the same.

A primary object of the invention is to provide an end post, which preferably initially consists of one or more layers of fabric of electrically non-conductive material made in sheet form from filaments or fibers, such as glass or other material, impregnated or coated with a suitable thermo-respousive resinous or elastomeric material.

When the sheet or sheets of resinous or similarly functioning material is dry, it is subjected to die cutting in a punch press, or the like, to conform in cross-sectional shape to the rail section with which it is intended to be used, for example, 90#, 100#, 129#, 131#, or the like. Depending on the thickness of the dry stock, the embryo end post may initially contain as many pre-fonmed layers as required to bring it ultimately into final form and thickness.

Another object is to provide an end post that is impervious to moisture and not affected by heat, pressure, or operating conditions, and which can be produced by simple stamping operations from pre-formed impregnated materials.

In the drawings:

FIGURE 1 is a fragmentary perspective view of a base sheet with the profile of the end post shown in dotted lines.

FIGURE 2 is a perspective view of a unit stamped out of the base sheet material.

Similar reference characters desginate corresponding parts throughout the several figures of the drawings.

The impregnated sheet of stock material A is more or less diagrammatically shown in FIGURE 1, but it may be of any desired practical and readily handahle commercial size, capable of being conveniently subjected to punching or stamping operations wherein, the die conforms to the cross-sectional shape of the rail section with which the end post is to be used. It will, of course, be understood that a single or multiple die may be used.

3,389,859 Patented June 25, 1968 As a result of the stamping operation, one or more of the embryo single units or layers B are thereafter assembled or stacked in registering juxtaposition to provide the desired thickness of the final end post, as shown in FIGURE 2. The assembly is then placed in a heated press to compact, fuse, and unify the adjacent units into a single homogeneous composite unit. The curing time depends on the characteristics of the coating on the fibers or filaments constituting the base of the sheet A.

When the layers are homogenized and cured, they are allowed to cool and are then removed from the press.

Materials with releated characteristics and curing times are set forth in my prior Patents 3,193,201, July 6, 1965; 3,288,369, Nov. 29, 1966; and 3,289,940, Dec. 1, 1966. Poly-urethane may also be used as the material for impregnating the woven fibers or filaments since the latter would have a tendency to stabilize and reduce its cold flow tendencies.

If desired, and for the most economical use of the sheet material, it is proposed that the die out be made larger than the largest end post, and of the most economical shape to utilize the entire width of the cloth sheet. Once the laminate is made, then the smaller area end post is either die cut or shorn from the shape previously cut from the primary layer to provide an end post of smaller size to fit rails of smaller cross-section. This system has the advantage of requiring only one die to make all sizes of end posts, plus the fact that the most advantageous use is made of the end post from the cloth.

In the above connection, it will of course be understood that the sheet A may originally be of a thickness equal to the desired final thickness of the end post, usually in the neighborhood of of an inch, in which case, if it is already cured, no heating is required.

I claim:

1. An insulating end post for railroad rails comprising, a unitary body having a contour corresponding to the profile of a given rail section, said body consisting of a plurality of superimposed layers bonded together by heat and pressure to the desired thickness to fully insulate adjacent rail ends from each other, and each said layer consists of a homogenous mass of fiber reinforced thermosetting plastic resin.

References Cited UNITED STATES PATENTS 2,808,995 10/1957 Degman 238153 3,312,399 4/ 1967 Cruikshank 104-1 1,622,614 3/1927 Stamos et al 238-152 FOREIGN PATENTS 1,025,318 4/ 1966 Great Britain.

ARTHUR L. LA POINT, Primary Examiner.

R. A. BERTSCH, Assistant Examiner. 

